CONTENTS

10 COMMON QUESTIONS ABOUT AUTOMATIC EVOLUTION OF FIRE STREAMS...... 2 NOZZLES EVOLUTION OF COMBINATION NOZZLES...... 3 1) How is an automatic nozzle different from a regular (conventional) UNDERSTANDING FIRE NOZZLE DESIGN ...... 5 nozzle? LIMITATIONS OF CONVENTIONAL NOZZLES...... 6 2) How does an automatic nozzle work? AUTOMATIC NOZZLES INVENTED...... 10 3) What pressure do we pump to automatic nozzles?

BENEFITS OF AUTOMATIC NOZZLES ...... 13 4) How do I know how much water I am flowing?

SLIDE VALVE vs. BALL VALVE ...... 16 5) What is the flow from each "Click Stop" on the nozzle?

TRAINING CONSIDERATIONS WITH AUTOMATICS ...... 18 6) Can I use automatics with foam and foam eductors?

USING LARGER SIZE ATTACK LINES ...... 21 7) Why don't all automatic nozzles have spinning teeth?

8) What type of nozzle is best for “Nozzleman Flow Control?” BOOSTER TANK OPERATIONS...... 22

SHAPING THE FIRE STREAM PATTERN ...... 23 9) Is it true that the stream from a "SOLID" bore nozzle hits harder and goes farther than the "Hollow”' stream from a fog nozzle? SMOOTH BORE vs. FOG TIP ...... 24

FLUSHING DEBRIS...... 28 10) What's all this talk about low pressure nozzles? What are the trade offs, is the compromise worth it? NOZZLE REACTION ...... 29

DUAL-FORCE/MID-FORCE ...... 34

Upon completion of this training booklet, you will be able to answer AUTOMATIC NOZZLES & FOAM...... 37 these, and many other, questions pertaining to firefighting nozzles. MASTER STREAM AUTOMATICS ...... 40 The ten questions and complete answers are listed in the appendix. THE WATER TRIANGLE CONCEPT ...... 42

CONCLUSION...... 44

LITERATURE 24/7 – Email or Fax ...... 45

APPENDIX ...... 46

FRICTION LOSS COEFFIEIENTS...... 58

FLOW AND REACTION CHARTS ...... 61

1

EVOLUTION OF FIRE STREAMS EVOLUTION OF THE COMBINATION NOZZLE (FOG NOZZLE) 17th Century (Bucket Brigades) The combination nozzle used today in the North Leather buckets were passed from person to person forming American fire service is a simple variation of the straight a line from the supply source to volunteers positioned near stream nozzle of the late nineteenth and early twentieth the fire. The water was applied, by the volunteers, in the best centuries. A standard smooth bore nozzle gives little in the way they could. way of stream choices. One diameter, one flow... @ 50 psi.

18th Century (Hose Companies) Leather hose and copper/brass playpipes. Sewn leather hose gave way to copper riveted hose. 1700's

19th Century (Engine & Hose Companies)

2.5" Cotton Hose & Underwriters Pipe (1888). To change streams required changing nozzle size. 20th Century 40's & 50's: 1.5" hose and assorted water spray nozzles.

50's & 60's: 1.5" hose combination, fixed and adjustable gallonage nozzles. 1800's

60's & 70's: 1.5" & 1.75” hose, automatic nozzle introduced The Introduction Of Stacked Tips by C.H. McMillan. Allowed Quick Accessibility To Four Tip Sizes

70's & 80's: 1.75" & 2.0" hose, wide spread acceptance of The Addition of a Baffle (disc) added two features: automatic nozzles. 1) Flow Adjustment

80's & 90's: Light weight 1.75" & 2.0" hose and introduction of dual pressure nozzles and special application attachments. 1940's & 50's 21st Century Lightweight 2.5” & 3.0” hose and introduction of safe, offensive portable monitor. The Baffle space changes for different gallonage.

3 2 UNDERSTANDING FIRE NOZZLE DESIGN

The purpose of any nozzle is to provide a restriction of the flow to build pressure. This restriction, and subsequent 1940's & 50's created pressure, provides a usable velocity to project the water stream. For any one flow, there is one correct nozzle size (restriction) to develop the optimum pressure and velocity. Nozzles come in a confusing number of sizes, shapes and styles. The large number of combinations greatly increases the possibility of hydraulics problems being Flow is determined by how far the baffle (disc) is from the encountered on the fireground. circular opening. The distance is preset in fixed gallonage combination nozzles and is changeable in adjustable gallonage nozzles.

2) Pattern Adjustment

1940's & 50's Fig. 7 SMOOTH BORES: • Fixed opening sized from 1/2" to 1-1/4" for handline firefighting operations • Larger stream (GPM) sized from 1-1/4" to 2"

Moving the shaper back widens the pattern. • For each flow, there is ONE CORRECT nozzle size to develop optimum velocity and reach

FOG NOZZLES: • Fixed or very limited gallonage selections • Require adjustments that limit nozzle performance 1940's & 50's • Require correct pump discharge pressure for best performance and GPM delivery

DESIGNED NOZZLE PRESSURES

Smooth Bore Nozzle - Handline - 50 PSI Moving the shaper forward focuses the water and a tight Smooth Bore Nozzle - Master Stream - 80 PSI solid stream can be achieved. Fog Nozzle (all types) - 100 PSI

4 5 Current conventional nozzles ("conventional" refers to a correct nozzle pressure, the proper flow (GPM), determined nozzle with a fixed size opening or manually adjustable by the correct pump discharge pressure, must be supplied opening) come in two basic types: 1. smooth bore and 2. (Fig. 9). peripheral jet, more commonly known as fog nozzles (Fig. 8). To allow for changing water conditions and to add greater flexibility (and often confusion), smooth bore nozzles are also available with stacked tips of increasing size.

Fig. 9

These flow requirements must include consideration of the available water supply, hose size and length, and the pumping capability of the supplying engine. IF all things go right, a given flow of water passes through the nozzle to produce the desired nozzle pressure and stream. A big IF!!!

If the proper fire stream is attained, the flow to that nozzle cannot be altered unless the discharge opening is changed Fig. 8 (manually adjusted) for the new flow, with a corresponding

adjustment in pump discharge pressure. Since conventional Many fog nozzles, booster through master stream, nozzles cannot change size, or are very limited in operate similar to a stacked tip by use of a gallonage ring adjustment, one of two things must happen. that manually adjusts the discharge opening (restriction) of the nozzle. Though manually adjusted tips improve the When a conventional nozzle is supplied less than the situation over fixed sizes (smooth bores), maximum rated flow, the result is a weak, less effective, stream. This efficiency is not achieved. Complete coordination between situation may be due to poor water supply, long hose lays, the pump operator, supplying the correct pump discharge improper selection of tip size, or pump operator error (Fig. pressure, and the nozzle operator is normally impossible. 10). This under-pressured stream may waste water, because Will the pump operator pump to a predetermined setting? If the velocity needed to reach the seat of the fire is not so, is the nozzle actually set to that position? Has the nozzle produced. This under pressure stream may cause the hose operator made a change in the setting, assuming that it will to kink more easily, therefore, reducing the flow even more! change the flow delivered? The problems multiply! It may jeopardize the safety of the nozzle crew. Little, if any, knockdown capability is achieved. Poor water supplies are LIMITATIONS OF CONVENTIONAL NOZZLES often blamed for poor fire streams. More often, poor streams result from the inability to match the correct nozzle In order for a conventional nozzle with a fixed opening size to the water supply that is available! (either smooth bore or fog) to operate at the

6 7

Fig. 10

On the other hand, if more than the required flow is being delivered to the conventional nozzle, excessive nozzle pressure will result (Fig. 11). This excessive flow will produce a proportionally higher nozzle pressure and, therefore, a corresponding increase in reaction, or "kickback".

Chart A

Any attempt to control the over-pressured line, by the nozzle operator cutting back at the nozzle, results in a fire stream that is broken and erratic. A partially open ball valve

Fig. 11 creates tremendous turbulence which reduces the stream's effectiveness. The nozzle crew must make a decision; fight The higher nozzle reaction will make the hose line more the hose line and the fire, or fight the fire with a broken, ineffective, stream. difficult to handle. It may jeopardize the safety of the nozzle crew in an environment that is already unsafe. This dramatic It becomes obvious when a handline is over pressurized. difference in nozzle pressure can be shown graphically What about a master stream device that is being operated at (Chart A). a pressure higher than normal? We can't "feel" the reaction or kickback. The high flow rate of a master stream device, added to the higher than normal pressure, may create a dangerously high nozzle reaction. This may add unnecessary stress to aerial ladders or elevated platforms.

In addition, the potential extra water available, evidenced by the high nozzle pressure, is not delivered effectively. A larger size nozzle for the extra water is required (changing the tip size). 8 9 The high flow, if delivered through the correct size opening, With current technology, the automatic transmission (the results in a reduction in nozzle reaction and also the required automatic pressure regulating nozzle) is now the method of engine pressure. choice. It is the simplest (from the operator's perspective), requires the least amount of specialized training, and is most What if there was a nozzle invented that would efficient at changing to the best gear at the proper time. For "automatically" size itself to the correct nozzle size for the whatever "speed" (flow) you choose, the automatic will GPM being delivered to it? adjust to give you the proper "gear" (flow opening).

AUTOMATIC NOZZLES INVENTED The automatic nozzle uses a principle very similar to that of a pumper relief valve. The pressure control mechanism The automatic nozzle, also referred to as a pressure- senses the pressure at the base of the nozzle (Fig. 12). regulating or a constant pressure nozzle, was developed in Slight adjustments are made automatically to maintain the the late 1960's by Chief C.H. McMillan of the Gary, Indiana, optimum nozzle pressure for the flow that is being delivered. Fire Task Force and founder of TASK FORCE TIPS, Inc. The nozzle was developed to solve the problems of using big streams with limited water supplies. A benefit of the automatic nozzle has been the many improvements of all aspects of firefighting involving water. This has resulted in new improved tactics, greater attack effectiveness, and greater flow deliveries than ever before possible.

For example, let's do a comparison that may make the automatic nozzle seem less mysterious.

A fixed gallonage or smooth bore nozzle is similar to using a manual transmission. As the vehicle speed (flow) increases or decreases, the correct gear (nozzle opening) must be selected and manually changed for proper stream quality.

The automatic nozzle is similar to an automatic transmission. Fig. 12 As the vehicle speed (flow) increases or decreases, the correct gear (nozzle opening) is automatically selected, The primary baffle, attached to the pressure control unit, producing proper stream quality all the time. varies the discharge opening of the nozzle (Fig. 13). In effect, the nozzle is constantly changing "tip size" to match the water being delivered. This allows the flow being supplied to be delivered at the proper nozzle pressure and correct velocity.

11 10 100 GPM @ 100 PSI BENEFITS OF AUTOMATIC NOZZLES

• Consistent hard-hitting streams • Correct nozzle pressure with available flow (GPM) NOTE: Baffle opening. • Maximum reach with available water • Capable of higher “initial attack” flows 200 GPM @ 100 PSI • “Nozzleman Flow Control” with patented slide valve

Consistent Hard-Hitting Streams NOTE: Change in baffle opening as gpm increases. To obtain the proper “punch” that is necessary for an 300 GPM @ 100 PSI aggressive attack, an automatic maintains the optimum nozzle pressure at all times. The fire stream pressure is unaffected by upstream variables that may be unknown to the pump operator or hose crew.

NOTE: Change in baffle opening as gpm increases. Proper Nozzle Pressure With Available Flow Fig. 13 With changing water supply, the automatic will adjust

This variable gallon-per-minute rating allows one to the flow available and use the water most effectively. If the automatic nozzle to take the place of many conventional flow to the nozzle is increased, the automatic will increase nozzles. An H-VPGI, TFT Handline, automatic nozzle with a the opening size to accommodate the larger flow. In flow range of 50-350 GPM, or a TFT Dual-Force with a flow situations where water supply is not adequate, or when range of 70-250 GPM, can be used on any size hose from sufficient lines have not been established to move the water 1-1/2" to 3". This wide flow range would require many available, the automatic will adjust to make best use of the different conventional nozzle sizes! supply until the system can be improved. If the water supply to the nozzle is reduced, the same nozzle pressure will The pressure-regulating principle used in the TFT continue to be maintained by decreasing the baffle opening Handline automatic nozzle is also used in the Ultimatic 125 size. Booster (10-125 GPM), the Mid-Matic (70-200 GPM) the Master Stream (150-1250 GPM), the Monsoon (300-2000 Maximum Reach With Available Water GPM) and the Typhoon (600-4000 GPM). The wide flow To gain the greatest reach with a fire stream, range of the Master Stream nozzle allows one nozzle to be maximum flow must be delivered at the correct velocity. By used, rather than a wide assortment of conventional fog or maintaining nozzle pressure (and velocity), the automatic smooth bore tips. nozzle will always produce the maximum reach possible with the available water supply. Unlike the conventional nozzles, the automatic allows for proper nozzle pressure under a variety of changing flow conditions.

12 13 Higher Initial Attack Flow Rates If the water is available, we normally attempt to deliver the rated capacity of the nozzle. More water can only be supplied to the conventional nozzle at the risk of a higher nozzle pressure and reaction. Excessive engine pressures would also be necessary to compensate for the increased friction loss and the higher than normal nozzle pressure. Fig. 14b

With an automatic nozzle, an increase in pump Nozzleman Flow Control discharge pressure is all that is necessary to move a higher Higher flow rates and pressure regulation are not the flow. The nozzle pressure remains constant; and the extra total answer and may present specific problems. Even with engine pressure is dissipated, as additional friction loss, pressure regulation, higher flow rates will produce higher producing a higher flow. nozzle reactions and, consequently, require better control of the flow by the hose crew. It may result in a greater waste of The difference between engine pressure and nozzle water, possibly causing greater water damage, if proper care pressure (with the valve fully opened) is the friction loss is not used. The total answer? The automatic nozzle MUST produced in moving the volume of water through a length of have “Nozzleman Flow Control”. hose. The basic formula for pump discharge pressure, PDP = NP + TPL (total pressure loss = appliance friction loss + The automatic pressure control mechanism and hoseline friction loss + elevation pressure), still applies. With patented slide valve within the nozzle allow the flow to be an automatic, the nozzle pressure remains constant and the regulated, up to the maximum that is supplied by the hose formula can be rewritten as PDP = 100 + TPL. layout, without affecting the nozzle pressure or stream quality. The use of the shutoff as a throttle also simplifies For example (Fig. 14a), a 150 foot 1-1/2" automatic operation. This gives the nozzle crew control that is not preconnect can move 170 GPM at 200 PSI engine pressure. otherwise available.

“Nozzleman Flow Control” with an exclusive turbulence-free slide valve, allows a nozzle operator to easily adjust the flow to what is needed or what can safely be handled. This has an effect of not only reducing fatigue and increasing safety, but it instills greater confidence in the Fig. 14a attack team. They know they have the higher flow rate, if needed; and a much more confident, aggressive attack can This is a 50% to 70% increase in flow when compared to a be made. conventional nozzle. When used with the same length of 1- 3/4" hose, automatics can easily flow 200 GPM for initial Individual nozzle crews can adjust their flow to what they attack (Fig. 14b). A higher flow rate from the first line on the need. Water use is kept to a minimum, and water damage fire can make the difference between success and failure. can be reduced (Fig. 15).

14 15

TFT Slide Valve The pressure control unit then compensates for the change of flow by moving the baffle to adjust the proper tip size, OFF maintaining correct nozzle pressure. Because of this action, the patented slide valve allows the nozzle to be operated at any handle position without producing turbulence that can affect stream quality.

• Stainless steel slide valve • Will not bind or tighten with age • Will not tighten under high pressures 1/2 THROTTLE • Is always easy to open

A Handline automatic, using a unique slide-type valve design, controls the flow WITHOUT creating turbulence (Fig. 16a). NOTE: Change in baffle opening.

FULL THROTTLE

NOTE: Change in baffle opening. Fig. 16a Fig. 15

Slide Valve vs. Ball Valve The pressure control then compensates for the increase or decrease in flow by moving the baffle to develop the proper Slide Valve tip size and pressure. A turbulence-free slide valve with This innovative slide valve has been proven in the automatic pressure regulation add up to “Nozzleman Flow Handline, Mid-Matic and Ultimatic styles. THIS VALVE Control”. DESIGN CONTROLS THE FLOW WITHOUT CREATING TURBULENCE. Ball Valve Ball valves have long stood as the primary means of

controlling water flow in the fire service. However widespread, they still retain problems which cannot be ignored.

16 17 • Designed to be operated in a fully open or fully closed When using the slide valve, the nozzle operator must position be aware that by using the shutoff handle as a throttle, the • Positioning other than fully open produces a violent flow can be gated back to a lower volume. And while working turbulence within the nozzle on ice, a roof ledge, a ladder, or any position where nozzle • Turbulence destroys the straight stream reaction is an added risk, the nozzle operator should throttle • Turbulence results in surging, disrupted fog patterns back to a safe, workable volume. The nozzle will (Fig. 16b) automatically adjust. The nozzle operator now has a valuable “in-between”! As nozzle pressure increases: Rather than calculating a desired pressure for a given • A ball valve becomes more difficult to open volume and hose layout (which is nearly impossible in the • The ball is forced harder and harder against the valve urgent rush of getting water), you simply pump to a standard seat level of pressure. Pump pressures of 150 to 200 PSI are suggested to deliver the increased, rapid knockdown flows. The flow control feature of TFT automatics allows the nozzle crew to then select the flow that is necessary. The difference in engine pressure and nozzle pressure (with the valve fully open) is the friction loss produced in moving the volume of water in that length of hose.

The basic formula for calculating engine pressure, Pump Fig. 16b Discharge Pressure = Nozzle Pressure + Total Pressure A nozzle, using a ball valve CANNOT control the flow without Loss (PDP = NP + TPL) still applies. creating turbulence. A ball valve is designed to work in the fully open position. Any attempt to operate in less than the TPL = Appliance Friction Loss + Hoseline Friction Loss fully open position, creates a violent turbulence within the + Elevation Pressure nozzle that results in poor stream quality and surging, With an automatic, the nozzle pressure will remain constant. disruptive fog patterns. The formula can then be more practically rewritten:

TRAINING CONSIDERATIONS WITH AUTOMATICS Pump Discharge Pressure = 100 + TPL

Any new technology or technique should be practiced Example: and perfected on the training ground if it is to be successful For a 500 ft. length of 2-1/2" hose, what engine pressure will in the heat of battle. Trained officers and firefighters are the be required to flow 300 GPM @ 100 PSI? single most important resource of a fire department Since appliance friction loss and elevation pressure loss are regardless of equipment used. not applicable: TPL = FL = CQ2L

18 19 FL = Hoseline friction loss in PSI The rule to remember is that automatics do C = Coefficient based on hose size EXACTLY as calculated with “standard” hydraulics Q = Flow in hundreds of GPM when calculations are correct. Natural laws cannot be L = Length in hundreds of feet violated. Where conventional calculations and assumptions

2 (such as available water) are incorrect, if conditions are such TPL = (2)(3) (5) PDP = 100 + TPL that desired calculations cannot be achieved, or other errors TPL = 90 PSI PDP = 100 + 90 are made, the automatic nozzle will compensate for the PDP = 190 PSI difference. The pressure control mechanism adjusts for the Rules of thumb, slide charts and tables (Appendix A) can be actual flow. This will provide the best possible stream for the used to convert a friction loss figure to a corresponding flow supply and conditions at that moment. Multiple streams are (Chart B). automatically coordinated and can be controlled to distribute the available volume most effectively. The pump operator should be aware that the pump discharge pressure will fluctuate as a result of the nozzle USING LARGER SIZE ATTACK LINES operator throttling the handline. Once the desired engine pressure is attained, the relief valve or governor should be People vary in size and strength and may work on set. Avoid “chasing” the pump pressure!! various footings. Sometimes no more than one or two firefighters are available to hold an attack line. To compensate for these variables, a nozzle with a wide flow range and “Nozzleman Flow Control” is essential. The question of larger attack lines and higher flow rates has received a lot of publicity in the past. Should we use them? Certainly, with an increase in hose diameter, there will be a marginal increase in the weight and size of an attack line. For its few drawbacks, the larger line has two overwhelming advantages. Firepower and Time! The 1-3/4" or 2" line, while retaining most of the handling benefits of the 1-1/2" line, approximate or exceed flows usually achieved of the standard 2-1/2". A 2-1/2" hose line is simply overkill for the flows a typical hose crew can hold.

Let's take for example: A certain fire will require 125 gallons of water to absorb the heat and to extinguish the blaze. With a booster line at 25 GPM, an application rate of five minutes or more will be necessary. A standard 1-1/2"

line flowing 125 GPM, requires 1 minute. A 1-3/4" line flowing 250 GPM requires only 30 seconds! Chart B

20 21 During the time of application, the fire generates additional A booster size line wouldn't have phased it, and a heat and consumes more fuel. Therefore, the lower rates conventional 1-1/2" flowing continuously might have taken (the 25 GPM booster, for example) may not stop it even after several minutes and several hundred gallons of water to the full five minutes. Firefighters can't press the attack. As control the first room, if at all. Two firefighters can maneuver the flow increases, the actual amount of water required will a 1-3/4" far more rapidly than four can muscle a 2-1/2". also decrease, so that the actual volume required will be Move-hit! Move-hit! Even the 500-gallon tank is significantly less than the expected 125 gallons. This is due spread out over the first critical minutes with unbelievable to the effect of the blitz attack--Hitting it hard and fast! results. By that time, a supply line from a hydrant or tanker Nozzles with “Nozzleman Flow Control”, in should be connected. If this blitz attack hasn't controlled the combination with larger size preconnected lines, add a new fire, or at least bought time to supplement the supply, NO dimension to the term "fire attack". Big line flows, with fast, WAY could an effective attack have been made with smaller small line handling are now available. Well-trained lines. firefighters and teamwork are still a must, but available personnel can now get in faster with more attack capability. SHAPING THE FIRE STREAM PATTERN

With 1-3/4" line at 200 PSI pump pressure, flows are The automatic nozzle shapes the fire stream from available up to: straight stream, for reach and penetration, to fog patterns,

230 GPM on 150 foot preconnects for greater heat absorption, firefighter protection, and 200 GPM on 200 foot preconnects specialized applications. However, there is more to shaping a fire stream than turning the bumper. 175 GPM on 250 foot preconnects

These flows are practical maximums for this size line. Fog or spray-type nozzles have been in use since the With “Nozzleman Flow Control”, these flows can be reduced 1940's. Most of these fog nozzles had one trait in common. at the nozzle to fit the need or situation. They all relied on stream impingement or some form of fog teeth to produce the wide fog pattern.

BOOSTER TANK OPERATIONS The earliest style of fog nozzles used had square- faced metal teeth (Fig. 17a). Two problems existed: 1) the At first one may cringe at such high flow rate square-faced teeth left gaps or "fingers" in the fog pattern capabilities or procedures. "But we've only got 500 gallons in which allowed heat to pass, and 2) the metal teeth were our tank!"; "Just two minutes on one line, one minute with a susceptible to damage when dropped or used as a "forcible pair!" With training and experience, that's not the way it entry tool". goes. After a quick preconnect stretch to the seat of the fire, a blitz attack flow is delivered. A 10-15 second blast The next generation of fog nozzles used spinning produces a tremendous effect, with steam penetrating the teeth (Fig. 17b) which appeared to eliminate the fingers of same channels as the fire. A room of intense fire can be the wide fog. The spinning teeth reshaped the fingers that quenched using only 50 or so gallons. By repositioning, were visible (high speed photographs show that they are still another shot can be delivered. there) with a wider and thinner fog pattern. 22 23 The wide, thin pattern spreads the available water out The latest innovation uses molded rubber fog teeth as beyond practical use. Maximum width should be just wide an integral part of the bumper. The strong, pliable fog teeth enough to cast a dense shadow of protection for the hose resist damage by springing back to their original shape after crew. All droplets are extremely fine and can be rapidly impact. The thick rubber bumper aids in protecting these fog carried away. Spinning teeth do not direct water to the center teeth, which are essential to producing a good fog pattern. of the pattern. The teeth are often made of plastic and are The use of computer-aided design in the development easily damaged or broken. of the TFT Handline automatic (released Sept.,1983) has A later development, the double row of teeth (Fig. allowed the creation of the only fog pattern that has full-fill to 17c), attempted to fill the gaps between the teeth by creating the cone without fingering (Fig. 18). Each fog tooth has been another point of deflection. However, the second row formed shaped to form a small nozzle with the proper stream spread "fingers" of its own and, therefore, left gaps in the pattern. so as to overlap the next tooth. The face of the bumper is specially engineered to "pull" the water to a wider pattern. The tremendous pulling effect can be seen when slowly moving from partial fog to the wide fog pattern.

17c

17b 17a

Fig. 18

The rubber tooth is designed to produce a wide range of droplet sizes, from moderately coarse to extremely fine. The pattern has maximum heat absorption, due to the fine droplets, yet produces large droplets for maximum reach and projection.

24 25 The combination of these two effects provides a A fog nozzle at proper operating pressure exits the densely-filled cone of water. This outer cone blends with the periphery at equal velocity across the stream. A partial inner ball of water created from the fronts of the fog teeth to vacuum within the pattern is created which will focus the form a "POWER FOG". stream together a short distance from the nozzle (Fig. 19b). The re-converged stream has a uniform cross-sectional For additional information, dial 800-348-2686 and talk to a velocity which results in a tighter, more coherent stream with nozzle specialist. more firefighting action.

SMOOTH BORE vs. FOG TIP

It is still mistakenly believed that for a high wind, or for maximum reach, a "straight stream" or "smooth bore nozzle" is required, though it does not have the flexibility of an adjustable fog nozzle. EQUAL VELOCITY OF FOG TIP By design, a fog nozzle at proper pressure will produce a straighter straight stream than a smooth bore tip. Fig. 19b

The foundations of tradition quake! Why? A smooth bore In all probability, many readers will be skeptical. So stream at correct operating pressure has a greater velocity we ask that you go out and prove it to yourself. A at the center of the stream than at the sides. This is due to PROPERLY TRIMMED peripheral fog nozzle delivers a the sidewall friction or turbulence of the water along the straighter, tighter, more far-reaching stream than the sides of the tip (Fig. 19a). As the water exits the nozzle, the "smooth bore". stream has a tendency to separate and peel away from itself. The stream is truly "solid" for only a few inches. At very low pressures, the separation is not as evident (the "glass rod"); however, the stream is totally ineffective for firefighting.

Fig. 20a

Fig. 19a Fig. 20b

26 27 The built-in inlet screen “Gasket Grabber” is located in the back of the nozzle and should be checked after each use. Any debris caught in the “Gasket Grabber” should be removed after each nozzle use.

Fig. 20c

Proper trim is the key, and that is the point where the pattern is just closed. For example, for the longest reaching, sharpest straight stream, the shaper sleeve is rotated toward fog until the pattern starts to widen (Fig. 20a); then it is Fig. 22 turned back enough to close the stream to parallel (Fig. 20b). To advance the shaper farther will cause the stream to NOZZLE REACTION cross over the focal point and degrade the stream (Fig. 20c). Considerable attention has been given throughout this FLUSHING DEBRIS booklet to nozzle pressures and the effects of reaction. Newton's Third Law of Motion states, "For every action there Another necessary feature of a fog nozzle is the is an equal and opposite reaction." Nozzle reaction is best ability to flush unwanted debris. Stones, gaskets, tank scale, known to firefighters as nozzle "kickback". Simply, at equal etc., can all seriously affect the operation of the nozzle. The nozzle pressures, a higher volume will have a higher pressure-assisted flush allows debris up to 5/16" to pass reaction. At equal flows, a greater nozzle pressure will through the nozzle by a simple twist of the shaper past wide produce a greater reaction. This law creates a problem with fog (Fig. 21). conventional non-automatic nozzles. Once the rated flow is

reached, slight increases in GPM produce rapid gains in nozzle reaction.

1-1/2" Fog Nozzles For example, let's look at a conventional 1-1/2 inch fog nozzle rated at 100 GPM. At the rated flow (100 GPM), the nozzle pressure would be 100 PSI. To increase the flow to 110 GPM, a nozzle pressure of 120 PSI would be required. For a flow of 120 GPM, the required nozzle pressure would be 145 PSI; and at 130 GPM, the nozzle pressure would be a whopping 170 PSI.

Fig. 21 29 28 To translate these nozzle pressure/flow combinations to 2-1/2" Fog Nozzles nozzle reaction, the following common formula is used for A conventional 250 GPM fog nozzle on 2-1/2" hose fog nozzles — NR = (0.0505)(Q√NP) exhibits the same reaction characteristics as the 100 GPM fog nozzle when operated above its rated flow. For example: Where: NR = Nozzle reaction in pounds 0.0505 = A constant 250 GPM = 126 lbs. NR (100 PSI NP) Q = Flow in GPM 275 GPM = 153 lbs. NR (+10% flow, +21% reaction) NP = Nozzle pressure in PSI 300 GPM = 182 lbs. NR (+20% flow, +44% reaction) 325 GPM = 214 lbs. NR (+30% flow, +70% reaction) With this formula we calculate that the nozzle reaction for each of the above flows is: Shown graphically in charts E & F.

100 GPM = 50 lbs. NR 110 GPM = 61 lbs. NR (+10% flow, +22% reaction) 120 GPM = 73 lbs. NR (+20% flow, +46% reaction) 130 GPM = 86 lbs. NR (+30% flow, +72% reaction)

With a conventional fog nozzle (Chart C), once the rated flow is attained, nozzle reaction will increase at a rate more than twice as fast as flow (Chart D).

Smooth Bore Tips Smooth bore nozzles are subject to the same rules for nozzle reaction as conventional fog nozzles. Both types of nozzles have a fixed size opening. Above the rated flow, the nozzle reaction will climb faster than the increasing flow. Neither will produce a significant increase in flow. The same nozzle reaction formula for fog nozzles can be applied to smooth bores, but is more commonly rewritten as:

31

30 NR = (1.57)(d2NP)

Where: NR = Nozzle reaction in pounds 1.57 = A constant d = Nozzle diameter in inches NP = Nozzle pressure in PSI

Smooth bore nozzle reaction also increases at a rate more than twice as fast as flow. In either case, with conventional nozzles, the nozzle reaction and pressure increase drastically to attain a marginal increase in flow.

Remember, the reason that the nozzle reaction increases so dramatically with conventional nozzles is that the nozzle pressure must increase with an increase in flow. The discharge opening does not change. The real culprit in nozzle reaction is the nozzle pressure!! Just from the information above, it makes sense to Automatic Nozzles use an automatic nozzle. With the formula that is used to Automatic nozzles have the ability to keep nozzle determine nozzle reaction for fog nozzles (NR = 0.0505 x Q reaction at a minimum for any given flow by maintaining a x √NP), and a constant nozzle pressure of 100 PSI, an easy constant nozzle pressure. rule-of-thumb calculation would then be NR = 1/2 GPM.

Using the same flows as the previously mentioned 2- The nozzle reaction from a fog nozzle will also vary 1/2" fog nozzle, and the same NR = (0.0505)(Q√NP) with the stream pattern. The greatest nozzle reaction will be formula, the nozzle reaction for an automatic would then be: in the straight stream pattern.

250 GPM = 126 lbs. NR As the nozzle reaction increases with any nozzle, an 275 GPM = 139 lbs. NR (+10% flow, +10% reaction) equal or greater amount of counter-reaction must be 300 GPM = 152 lbs. NR (+20% flow, +21% reaction) produced to keep the nozzle stationary. In most firefighting 325 GPM = 164 lbs. NR (+30% flow, +30% reaction) operations, this counter-reaction is supplied by the

Note that with an automatic nozzle (Chart G), the firefighting crew. (See Nozzle Reaction Chart at rear of increase in nozzle reaction is equal to the increase in GPM. book.) Just how much water can this team flow and still A 10% increase in GPM produces a 10% increase in nozzle maintain control of the hose line? From past experience and reaction. A 20% increase in GPM produces a 21% increase experimentation, flows of 150 to 250 GPM are workable in reaction, and a 30% increase in GPM produces an equal volumes for automatics on preconnected hose lines with a 30% increase in nozzle reaction (Chart H). two-person attack team.

32 33 Should the nozzle reaction become excessive for a lone operator, the TFT Automatic is the ONLY nozzle that allows the nozzle operator to adjust the flow and, therefore, the nozzle reaction without affecting the nozzle pressure or stream quality. Think about it the next time you are working on a ladder or other dangerous location. Varying firefighter capabilities and situations makes the ability to control flow and resulting reaction a vital necessity in using the higher flow rates to maximum advantage.

DUAL-FORCE / MID-FORCE (Dual-pressure Automatic Nozzle)

TASK FORCE TIPS created the first dual pressure automatic nozzle to address a new need in the fire service. This need is to allow the firefighter to override the automatic pressure control (100 PSI) and obtain an increased flow Standard Pressure Operation (GPM) at a lower nozzle pressure in certain situations. Fig. 23

This latest feature allows the nozzle operator to very quickly change the operating pressure of the nozzle from the "STANDARD" 100 PSI to a low pressure setting of about 60 PSI. By changing the Nozzle Pressure additional friction loss in the hose is overcome allowing more flow to pass. (Refer to DUAL-FORCE and MID-FORCE flow/pressure charts in appendix.)

Standard Pressure Operation The Dual Pressure Automatic nozzles have a redesigned pressure control unit that accurately and consistently maintains the desired nozzle pressure of 100 PSI, as specified in NFPA #1964 for automatic nozzles. The DUAL-FORCE has the unique distinction of being “the first automatic nozzle to meet NFPA #1964 flow standards for automatic nozzles”. Each nozzle has been completely tested for total compliance by both third party contractors and TFT's engineering staff. Complete test documentation is available Low Pressure Operation by visiting our web site www.tft.com. Fig. 24 34 35 Low Pressure Operation AUTOMATIC NOZZLES AND FOAM By a simple twist of the knob, located on the baffle at the front of the nozzle, the DUAL-FORCE and MID-FORCE Automatic nozzles can be used with great success for goes into low-pressure between 55 PSI and 75 PSI foam applications providing certain guidelines are followed. (depending on GPM flow). Foam-making is simply adding the proper amount of foam concentrate to water. This solution of concentrate and water NOTE: The initial opening of the DUAL-FORCE is then mixed with air (aeration) at the nozzle to form a opens wider to improve very low pressure operations. Think finished foam product. of the low-pressure mode as switching the nozzle to the equivalent flow of a 3/4" smooth bore. However, from 65 PSI Foam Type on up, instead of the nozzle pressure increasing drastically The types of foam that work well with a non-aspirated (like on a smooth bore), the DUAL-FORCE increases the fog nozzle (conventional or automatic) are synthetic AFFF opening as more GPM is delivered. The DUAL-FORCE acts foam, "Class A" and synthetic detergents. All foams will work much better when an aspirating attachment is used. like an elastic smooth bore increasing in size as the flow increases (Refer to the DUAL-FORCE flow/pressure chart in Foam Concentration appendix). Once the proper type of concentrate is selected, it must be mixed in the right proportion with water. Proper Low Pressure Setting Applications injection of foam concentrate with water is the single most There are certain fireground situations when important element to good foam-making. If a foam eductor is adequate pressure cannot be supplied to the nozzle. When used for foam proportioning, the nozzle flow must match the this occurs, the nozzle cannot "open up" and allow for capacity of the eductor, and the mixture setting on the adequate flow. We recognize that the ability to override the eductor must be set to match the foam concentrate. pressure control unit would be desirable in certain unusual situations. Foam Proportioning Eductors are pre-engineered systems and require This may include one or more of the following: specific pressures for operation. The eductor manufacturer's

1. Incorrect pump operation. recommendations for hose size, length, and pump pressure 2. Pump transfer valves jammed or not fully changed should be followed. The automatic nozzle will adjust itself to the GPM rating of the eductor. over. 3. Kinked hose line. 4. High elevation losses/long hose lays (high-rise). 5. "Pressure reducing valves" in high-rise building applications. 6. "Stolen" flow by conventional nozzles or large caliber streams. 7. Pumper breakdown/pump failure.

Fig. 25 36 37 With ANY eductor system, the nozzle valve MUST be fully Assuming operation will be from the pre-mixed open to allow proper flow across the eductor at the venturi. booster tank, the procedure will be similar to pulling a This produces the vacuum necessary to pick up the foam preconnect for structural firefighting. A 150 foot 1-1/2" line concentrate and mix it into the water. can have a foam flow of 150+ GPM at a pump pressure of 200 PSI; a 1-3/4" preconnect can flow 200+ GPM at the This can be used to your advantage if only water is same pump pressure. A pre-piped deluge gun with a Master needed at the nozzle. By partially throttling the nozzle, a can flow in excess of 400 GPM. This option allows back pressure is created at the eductor, and the foam considerably more knockdown potential than a 60 or 95 concentrate is not picked up, allowing for water only to be GPM eductor. Although this procedure may not be discharged at the nozzle. necessary for every situation, it does give large and small

fire departments high foam application rate capability without Batch Mixing additional specialized equipment. In addition, with the pre- The nozzle operator may operate the valve on the mixed method, the nozzle operator using a handline can now automatic nozzle in any desired position and the concentrate adjust his flow to what he needs, unlike operations with an ratio will remain constant at all flows. eductor.

Around-the-Pump Proportioning Systems To gain the maximum reach and, at the same time, High flow rates and multiple hose lines may be used. produce the maximum expansion ratio of the foam/water Like the single eductor, the nozzle operator MUST keep the solution, the nozzle should be adjusted to a very narrow 10- valve on the nozzle FULLY OPEN. 15 degree fog pattern. Wider fog patterns will result in a Discharge-Side Proportioning System thinner foam with a lower expansion ratio. The expansion The desired concentrate ratio is maintained at all flow ratio is the amount of finished foam produced to the volume rates up to the maximum capacity of the concentrate pump. of solution used to generate the foam. Foam manufacturers Once selected, the concentrate ratio will automatically be currently recommend an 8 to 1, up to 11 to 1, expansion injected into the water stream and will not be affected by ratio. For example, an 8 to 1 expansion ratio means 800 variations in hose, length, pressure, or elevation. The nozzle gallons of finished foam is produced from 100 gallons of the operator may operate the valve on the nozzle in any desired foam concentrate/water solution. position and the concentrate ratio will remain constant at all flow rates.

Nozzle Operation Now that we have the right type of foam mixed in the right proportion, with either discharge-side or around-the- pump proportioning, an eductor, pre-mixed in the booster tank, or some other method, let's focus on proper nozzle operation for optimum foam-making capability.

Fig. 26 38 39 With the use of a TFT Foamjet, TFT Foamjet-LX or moment? Can the proper pump pressure be determined TFT MX-Foamjet aspirating attachment, automatics will quickly for each layout? produce an expansion ratio between 8 and 14 to 1. The TFT Master Stream automatic nozzle was By maintaining a constant nozzle pressure, the developed out of the need to coordinate master streams at automatic will keep the velocity of the stream high. Large multiple alarm and mutual-aid fires. The water supply and amounts of air are pulled into the stream and mixed with the pumping capability at these incidents varied from unlimited foam/water solution at the end of the stream. This mixture of to virtually nonexistent. In addition, it was not unusual for the air and foam solution expands and "snowflakes" down lightly water supply to fluctuate as pumpers tapped into common on the burning surface. Additional expansion can be created sources or when relays were established to improve the by deflecting the foam stream on a horizontal or vertical supply. The scenario has changed little, but the automatic surface further entraining air and increasing the foam has had a significant effect on the outcome. expansion. A foam stream should not be directed into a Master Stream nozzles have a wide flow range of flammable liqued as this may cause splashing of the fuel and 150-1250 GPM. Like all automatics, the pressure control possible injury. TFT automatic handline nozzles have an mechanism of the Master Stream will maintain a nozzle excellent performance record when used for structural pressure of 100-105 PSI throughout the wide flow range of firefighting. If these guidelines are followed, they will perform the automatic nozzle. with excellent results as foam-making nozzles. The combination of the wide flow range and pressure MASTER STREAM AUTOMATICS control make the Master a practical choice for aerial ladders, aerial platforms, portable monitors and pre-piped deck guns. During major fire situations, the quick application of A single Master can take the place of several different nozzle large volumes of water is necessary to effect control and sizes (Fig. 27). extinguish the blaze. Larger fires will also require the resources of additional firefighters and equipment. The command and coordination of these units become increasingly difficult as the tactical plan is put into action. The incident commander soon realizes that the success of his strategy is largely dependent on the success of the fire streams.

In a fire situation where the water supply is known to be less than desirable, it would be necessary to begin the attack with a small tip size to deliver the available flow. If the water supply is improved, will the tip size again be changed to accommodate the new flow? What if the supply available is shared with other fire streams? Will the correct tip sizes be selected to make the best use of the water supply for that 40 Fig. 27 41 The coordination of master streams is greatly When pumping into an automatic nozzle, the pump simplified when using automatics. For additional information, operator throttles out until he reaches a limiting side of the dial 800-348-2686 and speak to a nozzle specialist. triangle. These limits would show as:

1) WATER SUPPLY: indicated by 5 - 10 PSI on the inlet THE WATER TRIANGLE CONCEPT gauge or by the suction hose going slightly soft. It can also The simplified hydraulics of the automatic nozzle can show as the engine tending to "run away" (speed up easily be remembered as a "Water Triangle" (Fig. 28). erratically).

2) PRESSURE: indicated by the limiting pressure, usually 200 - 225 PSI showing on the pumper discharge pressure gauge.

3) POWER: indicated by running out of throttle.

While these limits will yield the maximum for a particular layout, this is not to say that the layout shouldn't be improved! If working against the pressure limit, adding parallel or large-diameter lines will greatly increase flow. If water supply is the problem, improvement is necessary on the suction side of the pump. This can be accomplished with larger suction lines, additional lines into the pump, or receiving water from an additional source (relay pumping). The power limit is reached only at high volume, usually when supplying over-capacity to one or more streams. The load can be shared with a second pumper by shifting lines. The second pumper can be worked in tandem off the same hydrant with the first. Additional parallel or large-diameter lines can be used to reduce friction loss. Fig. 28 Although the same limits apply to a pumper when Each side of the triangle represents one of three limits working with "conventional" tips, merely working to the to any pumper setup. They are 1) water supply, 2) pumper system limit does not produce desired results unless the tip power, and 3) maximum allowable working pressure. size is exactly correct. If the regular tip size is too large, a Working the pumper to whichever of the limits is reached poor, under-pressured stream is all that can be obtained. If first produces the maximum possible delivery for that the regular tip is too small, the stream will be over- particular layout. pressured, failing to deliver the volume available using the correct size tip.

42 43 With automatic nozzles, the pump operator can achieve EMAIL & FAXABLE LITERATURE maximum efficiency as fast as he can adjust his throttle. The automatic is simultaneously adjusting the "tip size" to best With the implementation of TFT's ON LINE LIBRARY, you deliver the available water. can receive valuable information 24-hours a day through your computer or fax machine. All this is very simple: YOU DON'T FOOL MOTHER NATURE! Working with automatics will maximize Mother Information on new products, current products, maintenance Nature's laws to the ultimate with optimum results assured procedures, product specifications, product comparisons, faster and more accurately than with conventional nozzles. firefighting techniques, reports, and new ideas is as close as your fingertips.

CONCLUSION To access this service, go to www.tft.com and enter the On Line Library. Find the information you need and decide if you Increased fire loads, hazardous materials, and want to view it on line, email yourself a copy or send it to reduced personnel are serious problems which we face in your fax machine. the 21st Century and beyond. However, we must still respond. Saving lives and protecting property continue to be For additional information on our On Line Library or any our primary objectives. other firefighting topic, call 800-348-2686 and speak to a nozzle specialist. Recent changes in hose sizes for both supply and attack has allowed more water to be applied in less time. Only with an automatic nozzle will you benefit from these changes. The TFT family of automatics can improve your fire-suppression capabilities and, at the same time, simplify and standardize fireground operations.

An effective fire stream is the desired end result of any water, pump, hose, and nozzle combination. The automatic assures you of this by making constant adjustments to match the current water supply.

No matter how fine your firefighters, equipment or training, the success of your efforts depends on the working ends of your hose lines. Either you have the best possible streams with maximum control, or the rest of your efforts are in jeopardy.

For additional information, call 800-348-2686 and speak to a nozzle specialist.

44 45 APPENDIX In addition, the potential extra water available, evidenced by the high nozzle pressure, is not delivered effectively. A large 10 Common Questions About Automatic Nozzles size discharge orifice for the extra water is required 1) How is an automatic nozzle different from a regular (changing gallonage setting). The high flow, if delivered to (conventional) nozzle? the correct size opening, results in a reduction in nozzle Conventional fog nozzles are nozzles that have a fixed or reaction, a reduction in the pump pressure, and produces a selectable GPM setting. These GPM settings correspond to fire stream at the proper pressure. With an automatic nozzle, a particular discharge orifice or "tip size". In order for a the discharge orifice is continually variable depending on the conventional nozzle with a fixed opening to operate at the flow to the nozzle. This allows the flow being supplied to be correct nozzle pressure (100 PSI), the proper flow (GPM) delivered at the proper nozzle pressure and correct velocity must be supplied. For example, a selectable gallonage for maximum extinguishing capability. Some of the benefits nozzle with settings of 30-60-95-125 GPM will only deliver of automatic nozzles are as follows: these flows at 100 PSI nozzle pressure. Constant Hard-Hitting Streams: To obtain the proper

If the proper fire stream is attained, the flow to that nozzle "punch" that is necessary for an aggressive attack, an cannot be altered unless the discharge opening is changed automatic maintains the optimum nozzle pressure at all for the new flow (larger for a higher flow and smaller for a times. The fire stream is unaffected by upstream variables lower flow). Since conventional nozzles cannot change size that may be unknown to the pump operator or hose crew. and are limited in adjustment, one of two things must Proper Nozzle Pressure With Available Flow: With happen. changing water supplies, the automatic will adjust to the flow The first possible result occurs when the conventional nozzle available and use the water most effectively. If the flow to the is supplied less than the rated or selected flow. This results nozzle is increased, the automatic will increase the in a weak, ineffective stream. The situation may be due to discharge opening to accommodate the higher flow. In poor water supply, long hose lays, improper selection of tip situations where water supply is not adequate, or when size, or pump operator error. This under-pressured stream sufficient lines have not been established to move the water may waste water because the velocity needed to reach the available, the automatic will adjust to make best use of the seat of the fire is not produced. Little, if any, knockdown supply until the system can be improved. If water supply to capability is achieved. the nozzle is reduced, the automatic will decrease the size of the discharge orifice and the same nozzle pressure will The second possible result occurs when the conventional continue to be maintained. nozzle is supplied more than the rated or selected flow. This results in excessive nozzle pressure. The excessive flow will Maximum Reach With Available Water: To gain the produce a much higher than normal nozzle pressure and, greatest reach with a fire stream, maximum flow must be therefore, a corresponding increase in reaction or "kickback". delivered at the correct pressure. By maintaining the nozzle This higher reaction will make the hose line more difficult to pressure at 100 PSI, automatic nozzles will always produce handle and may jeopardize the safety of the nozzle crew. the maximum reach possible with the available water supply.

46 47 Higher Initial Flow Rates: The limiting factor to maximum With an automatic, the nozzle pressure will remain constant flow delivery with conventional hose lines is usually the and the formula can be rewritten as: PDP = 100 + TPL. nozzle. If the water is available, we normally attempt to Example: For a 200 foot preconnect of 1-3/4" hose, what deliver the rated capacity of the nozzle. More water can only pump pressure will be required to flow 150 GPM? (Friction be supplied to the conventional nozzle at the risk of higher loss in 1-3/4" hose for 150 GPM is about 28 PSI per 100 feet nozzle pressure and kickback. Excessive pump pressures of hose.) would also be necessary to compensate for the increased friction loss and the higher than normal nozzle pressure. PDP = NP + TPL With an automatic nozzle, an increase in pump pressure is PDP = 100 + TPL all that is necessary to move a higher flow. The nozzle PDP = 100 + (2 x 28) pressure remains constant; therefore, the extra engine PDP = 100 + 56 pressure overcomes additional hose friction loss produced PDP = 156 by the higher flow. To flow 150 GPM in the above layout, a pump discharge

pressure of 156 PSI is required. The required pump pressure 2) How does an automatic nozzle work? will vary depending on the friction loss produced, the amount The automatic nozzle uses a principle very similar to that of of flow desired, and the length and size of the hose lay. Your a pumper relief valve. A highly dependable spring, department can determine specific pump pressures in connected to the baffle which forms the discharge orifice, is advance for various flows required for different operations. A balanced against the water pressure in the nozzle. The well-involved house fire will require a higher pump pressure pressure control (spring) senses the increase or decrease in for initial knockdown than the same fire during the overhaul pressure within the nozzle. It then moves the baffle in or out stages. to maintain a particular "tip size" necessary to keep the nozzle pressure at 100 PSI. In effect, the nozzle is Once standard operating procedures (SOP’s) are constantly changing "tip size" to match the water being established, standard friction loss tables for various hose supplied at that moment. This allows the flow being supplied lines can be used to develop pump discharge pressure to be delivered at the proper nozzle pressure and velocity. criteria based on the PDP = NP (100) + TPL formula. One

department in particular, that uses 200 feet of 1-3/4" 3) What pressure do we pump to automatic nozzles? preconnects, uses the following SOP for pump discharge Automatic nozzles greatly simplify pump operation. Since pressure... 200 PSI for initial attack when a working fire is automatic nozzles are designed to operate at 100 PSI nozzle found with a visible flame, 150 PSI when nothing is showing pressure, this becomes the minimum starting point for any and a line is taken in for investigation, and 125 PSI during operation. The basic formula for calculating pump discharge overhaul. These pump discharge pressures will provide flows pressure is PDP = NP + TPL, where PDP is the pump of approximately 200 GPM, 150 GPM and 125 GPM discharge pressure, NP is the nozzle pressure, and TPL is respectively. the total pressure loss (hoseline friction loss + apparatus friction loss + elevation pressure).

48 49 The advantage of using TFT automatic nozzles, in the The rule to remember is that automatics do exactly as previous application, is that any flow can be delivered by the calculated using "standard" hydraulics. Natural laws cannot pump operator and still be controlled by the nozzle operator. be violated. Unlike conventional nozzles where the nozzle Variable flow, constant nozzle pressure, and “Nozzleman pressure changes with the GPM flow, automatics will Flow Control” are three essential elements to successful fire maintain the nozzle pressure at 100 PSI. This known factor streams and fire attack. can be "plugged in" to the standard formulas to deliver a certain amount of water, or be used to determine the flow 4) How do I know how much water I am flowing? when pump pressure and hose lay are known. Much of the information in question three can be used to determine flow from the nozzle using standard hydraulics 5) What is the flow from each "Click Stop" on the calculations. We have already determined that, with an nozzle? automatic nozzle, the nozzle pressure will remain at or near All TFT handheld automatic nozzles have a feature called 100 PSI. By subtracting the known nozzle pressure of 100 "Nozzleman Flow Control". The slide valve in these nozzles PSI from whatever the pump discharge pressure is is unique. In addition to acting as a shut-off valve, it can also (assuming there is no pressure loss due to elevation), the be used to regulate the flow at the nozzle without affecting friction loss can be determined. By dividing the friction loss the stream quality. The handle, on these nozzles, controls by the number of hundred feet of hose in the hose lay, a the valve movement and, therefore, the flow. Where the value for friction loss per hundred feet is determined. This handle contacts the valve body, a series of six detents act to can then be compared to any standard friction loss chart for maintain handle position at any of the selected settings. the size of hose being used and a corresponding flow found. Moving the handle from the fully closed position, six detents For example: A hose lay consisting of 300 feet of 2-1/2" hose or "click stops" are felt. Since TFT standard and dual- and an automatic nozzle is being pumped at 145 PSI. The pressure automatics are variable flow nozzles, the maximum first step is to subtract the known nozzle pressure of 100 PSI flow (fully open) is determined by the pump engine pressure (for automatics) from the pump discharge pressure (145 - and hose lay. It is possible for the same handline automatic 100). This leaves 45 PSI for friction loss. The next step is to nozzle to flow 95 GPM if used on a 1-1/2" line, or as high as divide the friction loss by the number of hundred feet of 300 GPM if used on a 3" line. Because the maximum flow is hose; in this case, 45/3 = 15, or 15 PSI friction loss per 100 different each “click stop” would have a different value. foot of hose. By referring to a standard friction loss chart for Changing the engine pressure on the same 3” line to get a 2-1/2" hose, 15 PSI loss per hundred feet corresponds to a maximum flow of 200 GPM, will again change the flow at flow of 250 GPM. (All we have done is rearrange the formula each "click stop". used in question three to determine pump discharge The “click stops” were not developed to have specific flows pressure.) from each setting, but rather to maintain handle position as Then PDP = NP + TPL becomes TPL = PDP - NP; and since the nozzle operator reduced or increased the flow at the NP is always 100 PSI with automatics, it is more simply handle. written as TPL = PDP - 100.

50 51 6) Can I use automatics with foam and foam eductors? The spinning teeth reshaped the “fingers” that were visible If the eductor manufacturer's recommendations for inlet (high speed photographs show that they are still there), but pressure, maximum hose length and size are followed, the produced a wider, thinner fog pattern with little or no water in automatic nozzle will adjust itself automatically to the rating the center of the pattern directly ahead of the nozzle crew. of the eductor. With ANY eductor system, the nozzle valve The wide, thin fog pattern is not wide enough to protect the MUST be fully open to prevent excessive back pressure on hose crew while delivering the maximum amount of water the eductor which will prevent foam concentrate pickup. ahead of them for protection. All droplets are extremely fine, and are rapidly carried away under intense heat. These teeth TFT automatic nozzles can be used with great success are often made of plastic and are easily broken. when used for foam application. Certain guidelines, however, must be followed. Foam-making is simply the addition of a A later improvement, the double row of teeth, attempted to proper amount of foam concentrate to water. This solution of fill the gaps between the teeth by creating another point of foam concentrate and water is then mixed with air (aeration), deflection. However, the second row of teeth created either at the nozzle with air-aspirating attachments, or as the “fingers” of its own and, therefore, left gaps in the pattern. stream pulls air along with it, in a non air-aspirating Task Force Tips was the first to use rubber fog teeth as an application. integral part of the bumper. The thick rubber bumper aids in 7) Why don't all automatic nozzles have spinning teeth? protecting the fog teeth which are strong and pliable, TFT automatic nozzles shape the fire stream from straight resisting damage by springing back to their original shape stream, for reach and penetration, to fog patterns, for greater after impact. The use of computer-aided design has allowed heat absorption, firefighter protection, and special TFT to create the only fog pattern which is sufficiently wide applications. However, there is more to shaping a fire enough for crew protection while filling the center of the fog stream than turning the bumper. cone without “fingering” to the fog pattern. Each tooth has been shaped to form a small nozzle with the proper stream Fog or spray-type nozzles have been in use since the spread to overlap the next tooth. 1920's. Most of these fog nozzles have one trait in common.

They all rely on stream impingement or some form of fog 8) What type of nozzle is best for “Nozzleman Flow teeth to produce the wide fog pattern. Control”? The earliest style fog nozzles used square-faced metal teeth. Let's look at the three common nozzle types: fixed gallonage Two problems existed: 1) The square-faced teeth left gaps (smooth bores), adjustable gallonage, and automatics. or “fingers” in the fog pattern which allowed heat to pass, The fixed gallonage (smooth bore) nozzle offers the nozzle and 2) The metal teeth were susceptible to damage when operator two choices, on or off. A ball valve shutoff device the nozzle was dropped or used as a “forcible-entry tool”. that is partially opened creates tremendous turbulence which The next generation of fog nozzles used spinning teeth destroys the stream and greatly reduces its effectiveness. which appeared to eliminate the “fingers” of the wide fog. The pump discharge pressure must be matched to the nozzle by the pump operator.

52 53

A selectable gallonage, “flow controlling ring”, nozzle has the 9) Is it true that the stream from a "SOLID" bore nozzle same ball valve problems as the fixed gallonage (smooth hits harder and goes farther than the "Hollow”' stream bore), plus a misconception created by the “flow controlling from a fog nozzle? ring”. For example: A nozzle with a 30-60-95-125 selectable Absolutely false! And if you read to the end of this paragraph “flow controlling ring” set at 60 GPM, with a 100 PSI nozzle you will learn a method to prove this to not only yourself but pressure, and the ball valve fully open, will flow a usable anyone that believes this oldest of fire fighting myths. The stream. Simply turning the “flow control ring” to 95 GPM, fog nozzles stream is hollow for the first few inches of its lowers the nozzle pressure, produces an under pressurized reach and it is from this fact that the myth got its start. The stream, may waste water, reduces stream reach, reduces purpose of this short hollow section is to PREVENT the rest knockdown effectiveness, and does not mean you are of the stream from being hollow. By bringing the water to the flowing 95 GPM. Conversely, turning the “flow control ring” to outside and then FOCUSING it back into the middle the 30 GPM, results in excessive nozzle pressure and a stream is made parallel and hence its tendency to spread is corresponding increase in reaction or “kickback”! This higher stopped. A smooth bore on the other hand is squeezed nozzle reaction makes the hose line more difficult to handle down progressively until the instant that it leaves the orifice. and may jeopardize the safety of the nozzle operator. To A smooth bore stream can ONLY expand from the instant maintain proper nozzle pressure would require constant that it leaves the nozzle. Now, for the method of proving this. coordination with the pump operator and a pressure gauge All that is needed is a pitot gage and a flow meter or some mounted behind the nozzle. A selectable nozzle can be other means for being CERTAIN that the flow out of the two compared to an automobile's 4-speed manual transmission. nozzles to be compared is identical. (they will be at different

A TFT Automatic, with patented “slide valve”, offers true nozzle pressures, the smooth bore at 50 psi and the fog “Nozzleman Flow Control”. The slide valve allows the nozzle nozzle at 100 psi) First establish the flow on the smooth bore operator to decrease or increase the flow (GPM) without and pitot the nozzle to make sure that its at 50 psi. Note its creating turbulence. Because it's an automatic, the nozzle flow from the flow chart. Now move the pitot gage away from pressure remains constant at 100 PSI. This means, that for the nozzle attempting to maintain the highest reading any flow selected by the nozzle operator, the stream will be possible. You will find that it will be difficult to get any reading clean and properly pressurized, allowing the maximum reach above a few PSI. Now change nozzles to the fog nozzle (It possible for that flow. An automatic nozzle can be compared can be any kind of fog nozzle automatic or non automatic, a to an automobile's automatic transmission. manually set fog nozzle set to the same flow as the smooth bore might be easiest for this test as it will allow you to The ultimate “Nozzleman Flow Control” would be the TFT quickly set the base pressure to 100 psi to assure that an Dual-Force or Mid-Force (dual-pressure automatic). This equal flow is being compared) Adjust the fog nozzle for its automatic nozzle offers one more advantage over all other best straight stream which is the point where the nozzle just automatics. As an automatic transmission has the ability to closes from a narrow fog without crossing over. Now again be locked into low gear, for certain situations, the TFT Dual- use the pitot gage to measure pressure. At the very front of pressure automatics allow the nozzle operator to switch into the nozzle it will be difficult as the wall of water is quite thin, “low pressure” as the situation demands. move away from the nozzle to a distance of about 36 inches and hold the pitot in the stream. 54 55 You should be able to easily pitot 40 to 60 psi at this Make a comparison to the trend of our police departments in distance from the nozzle. So there is the proof, which is the the United States. As the threat to police officers goes up are "Hollow Stream" the one that can't be pitoted a few inches they going to smaller guns, fewer bullets in the clip? Are they from the nozzle or the one that can be pitoted 3 feet away taking out the bullets and pouring out half the powder? If and still have more pressure than the smooth bore. It’s an they cut out half the powder the gun would kick less, be easy choice to make. easier to aim, and it wouldn't hit as hard. Is that what the police want for their weapons? Is this what fire departments 10) What's all this talk about low pressure nozzles? really want for their primary weapon? Or what about an What are the trade offs, is the compromise worth it? example that comes closer to home, how many people wish The final decision on this must be left with the individual for a shower with less pressure and how many would think department but it is important that the facts be considered that a shower with less pressure does a better job of getting when the decision is made. True enough, reducing nozzle the soap off? pressure does account for some reduction in nozzle

reaction. But how much reduction in pressure is required to

get a significant reduction in reaction? And while reduced

reaction may be a good positive aspect what are the

negative aspects of choosing a low pressure nozzle delivery

system? First of all lets consider the amount of reduction in

reaction. The nozzle reaction is composed of two factors,

pressure and volume which are related by the formula

Reaction = .0505 x Flow x Square Root of Pressure. Many

are advocating reducing the fog nozzle pressure by 1/4 from

100 PSI down to 75 PSI. If the flow is kept constant the

reaction reduction from a 25% cut in nozzle pressure is 13%.

(For example a 200 GPM stream at 100 psi has 101 pounds

of reaction, cutting the nozzle pressure to 75 PSI only

reduces the reaction to 88 pounds). Nozzle pressure is

directly related to the VELOCITY or SPEED of the stream.

So now instead of a stream speeding through the super

heated gases at 80 miles per hour it goes through at 60

miles per hour. Which has more impact when it hits, a

baseball thrown by a major leaguer player at 80 mph or a

ball thrown by a little leaguer at 60 miles per hour? Which

goes further? Which splashes more when it hits, which bores

through the char to get to deep seated heat? The questions

go on and on, if its ok to cut the pressure in half then why not

cut it down to nothing, take the nozzle off, lay the hose in the

window, and fill the building up? 57 56 TPL=FL+EP+AFL TABLE 1

FRICTION LOSS COEFFICIENTS -- SINGLE LINE FL = Hoseline friction loss in PSI EP = Elevation Pressure Hose Diameter AFL = Appliance friction loss in PSI and Type (inches) Coefficient (C) HOSELINE FRICTION LOSS:

3/4" booster 1,100 FL = CQ2L 1" booster 150 1-1/4" booster 80 FL = Hoseline friction loss in PSI 1-1/2" rubber line 24 C = Friction loss coefficient (from Table 1) 1-3/4" with 1-1/2" couplings 15.5 Q = Flow rate in hundred of GPM (Q = GPM/100) 2" rubber lined with 1-1/2" couplings 8 L = Hose length in hundred of feet (L= Feet/100) 2-1/2" rubber lined 2 ELEVATION PRESSURE: 2-3/4" with 3" couplings 1.5 3" with 2-1/2" couplings 0.8 EP = .5H 3" with 3" couplings 0.677 3-1/2" 0.34 .5 = A constant 4" 0.2 H = Height in feet 4-1/2" 0.1 NOZZLE REACTION: 5" 0.08 6" 0.05 Smooth Bore Nozzle Standpipes NR = (1.57) (d2NP) 4" 0.374 5" 0.126 NR = Nozzle reaction in pounds 6" 0.052 1.57 = A constant d = Nozzle diameter in inches Reprinted with permission from the Fire Protection Handbook, Copyright 1986, NP = Nozzle pressure in PSI National Fire Protection Association, Quincy, MA. 02269.

Fog Nozzle PUMP DISCHARGE PRESSURE:

NR = (0.0505) (Q √NP) PDP = NP + TPL

PDP = Pump discharge pressure in PSI NR = Nozzle reaction in pounds NP = Nozzle pressure in PSI 0.0505 = A constant TPL = Total pressure loss in PSI Q = Flow in GPM (Note: This is not gpm/100) NP = Nozzle pressure in PSI 59 58 As a rule of thumb, use the following nozzle pressures to ensure safety and efficiency:

Solid Bore Nozzle (Handline) -- 50 PSI Solid Bore Nozzle (Master Stream) -- 80 PSI Fog Nozzle (All Types) -- 100 PSI

Pressure loss for elevated master streams and turret pipes will vary depending on the manufacturer of the device.

60

NOTES

LTT-010 January 17, 2001 Rev 2